WU Yuxiang, WANG Xinhui, CHAI Kungang, et al. Oxidized modification of novel silkworm excrement-based porous biocarbon with various acids for sustained release of pesticide thiamethoxam[J]. CIESC Journal, 2018, (6): 2797-2804.
DOI:
WU Yuxiang, WANG Xinhui, CHAI Kungang, et al. Oxidized modification of novel silkworm excrement-based porous biocarbon with various acids for sustained release of pesticide thiamethoxam[J]. CIESC Journal, 2018, (6): 2797-2804.DOI: 10.11949/j.issn.0438-1157.20171357.
Oxidized modification of novel silkworm excrement-based porous biocarbon with various acids for sustained release of pesticide thiamethoxam
Oxidation modification of a novel silkworm excrement-based porous carbon (SCSE) with various acidic oxidants were prepared and applied for sustained release of pesticide thiamethoxam (TM). The effects of pore size and surface properties on TM adsorption performance of SCSE and modified SCSE were investigated. The TM adsorption equilibrium/kinetics and release kinetics on four SCSE samples were systematically measured
and the corresponding kinetic parameters were estimated by using pseudo-first-order equation in two sections. The results show that:the prepared SCSE shows a micro/mesopores structure (1290.95 m2/g and 0.690 cm3/g) and its adsorption capacity of TM reached 560 mg/g at 298 K. The total controlled-release process for TM on the SCSE samples could be divided into two stages:fast-sustained release stage and slow release stage. The release rate for the fast-sustained release stage was about 29-34 times faster than that for the slow release stage. Among which
the SCSE-HN modified by HNO3 showed the highest release ratio and fastest release rate due to its largest pore size distribution and the weakest interaction towards TM. According to actual TM using conditions for some crops (1.0-2.0 mg/m2)
only 0.5 g of TM loaded PCSE can efficiently control main pest of crops per square meter last for over 40 days.